Segment:
Compact Executive Sports Sedan/Coupe
Competitors:
Porsche 944, Mercedes-Benz 190E 2.3-16/2.5-16 Evolution, Ford Sierra RS Cosworth, Nissan Skyline GT-R (R32)
Unique Selling Points:
Homologation special for motorsport, distinct body kit and wider track, advanced engine technology for its era, legendary handling and driver engagement.
Performance Focus:
Designed for homologation for Group A touring car racing, prioritizing performance and handling.
Design Evolution:
Based on the E30 3 Series, but with unique M-specific bodywork, suspension tuning, and engine.
Manual Value Proposition:
Provides essential, in-depth technical information for maintaining and repairing a classic M car, crucial for preserving its performance and value.
Market Focus:
Global (primarily European and North American markets)
Vehicle Variants Covered:
M3 Coupe (E30), Convertible (E30)
Estimated Page Count:
Varies by specific edition, typically 500-1000+ pages
Type:
Workshop Service Repair Manual
Powertrain:
Engine mechanical, fuel system, ignition system, cooling system, exhaust system, engine management (DME), transmission (manual and automatic options), clutch, driveshafts, differential, axles
Chassis:
Suspension (front and rear), steering system, braking system (ABS details), wheel bearings, subframes
Electrical:
Wiring diagrams, battery, alternator, starter, lighting systems, instruments and indicators, power windows, central locking, radio, ancillary electronics
Body:
Body panels, doors, windows, bumpers, interior trim, seats, sunroof (if applicable), convertible top mechanism (if applicable)
Routine Maintenance:
Oil changes, filter replacements, spark plug replacement, belt adjustments, fluid checks and top-offs, brake pad inspection
Repair And Rebuild:
Engine rebuild procedures, transmission overhaul, suspension component replacement, brake caliper rebuilding, steering rack repair, electrical component diagnostics and replacement
Diagnostics:
Troubleshooting guides based on symptoms, diagnostic trouble codes (DTCs) interpretation for DME, circuit testing methods
Technical Specifications:
Torque specifications, measurement data, clearances, timing settings, electrical resistance values
Level Of Detail:
Comprehensive, suitable for professional technicians and experienced DIY enthusiasts. Covers complete overhaul and diagnostic procedures.
Configuration:
Inline 4-cylinder
Displacement:
2.3 Liters (2302 cc) for S14B23, 2.5 Liters (2467 cc) for S14B25 (M3 Evolution)
Valvetrain:
Dual Overhead Camshafts (DOHC), 4 valves per cylinder
Bore X Stroke:
91.0 mm x 77.0 mm (S14B23), 95.0 mm x 87.0 mm (S14B25)
Compression Ratio:
10.5:1 (S14B23), 10.3:1 (S14B25)
Horsepower:
192-215 hp (S14B23), 238 hp (S14B25 - Evolution II)
Torque:
230-240 Nm (S14B23), 245 Nm (S14B25 - Evolution II)
Fuel Delivery:
Bosch L-Jetronic or Motronic (depending on year/market)
Fuel Type:
Premium Unleaded Gasoline (98 RON recommended)
ECU:
Bosch Motronic DME (Digital Engine Electronics)
Type:
5-speed Getrag 265 (dogleg manual)
Type:
ZF 4HP22 4-speed automatic (less common on M3)
Clutch:
Hydraulically actuated single dry plate clutch
Differential:
Limited Slip Differential (LSD) standard
First Gear:
3.72:1 (typical for dogleg)
Final Drive:
3.15:1 or 3.25:1 (typical)
Length:
Approx. 4416 mm (173.9 in)
Width:
Approx. 1700 mm (66.9 in) standard E30, 1730mm (E30 M3)
Height:
Approx. 1370 mm (53.9 in)
Wheelbase:
Approx. 2565 mm (101.0 in)
Curb Weight:
Approx. 1200-1300 kg (2645-2866 lbs)
Gross Vehicle Weight:
Approx. 1700 kg (3748 lbs)
NHTSA Rating:
Not directly rated by NHTSA for this era, but E30 platform generally considered robust.
ABS:
Anti-lock Braking System (ABS) available/standard on later models
Brake System:
Four-wheel disc brakes (ventilated front discs)
Seatbelts:
Three-point inertia-reel seatbelts
Body Construction:
Reinforced safety cell, crumple zones
Radio:
Factory fitted BMW Bavaria C, Business, or Professional radios with cassette player.
Speakers:
Typically 4-6 speaker system.
ABS:
Anti-lock Braking System (optional/standard depending on year).
Auxiliary Input:
Not present in original factory configuration; aftermarket solutions are common.
Oil Change:
Every 10,000-15,000 km (6,000-9,000 miles) or annually, whichever comes first.
Filter Replacement:
Oil filter with every oil change. Air filter every 20,000-30,000 km (12,000-18,000 miles). Fuel filter every 30,000-50,000 km (18,000-30,000 miles).
Spark Plugs:
Every 30,000-40,000 km (18,000-25,000 miles).
Valve Adjustment:
Every 40,000-60,000 km (25,000-37,000 miles) – shims require replacement.
Engine Oil:
SAE 10W-40 or 10W-50 synthetic or semi-synthetic (API SG/SH or ACEA A2/A3) – check manual for specific BMW LL rating for the era.
Coolant:
BMW Blue Antifreeze/Coolant (G48 ethylene glycol based) mixed 50/50 with distilled water.
Transmission Fluid:
BMW MTF LT-2 for manual transmission; ATF Dexron III for automatic transmission.
Differential Fluid:
SAE 75W-90 Synthetic Gear Oil (API GL-5)
Rust:
Common areas include wheel arches, sills, door bottoms, trunk floor, and shock towers.
Engine Misfires:
Can be caused by aging ignition coils, spark plug wires, fuel injectors, or distributor cap/rotor.
Suspension Wear:
Bushings (control arm, sway bar), ball joints, and shock absorbers are common wear items.
Headgasket:
While not as prevalent as in some other BMW engines of the era, overheated engines can develop head gasket issues.
ABS Sensor Failure:
ABS sensors can fail over time, leading to ABS warning lights and loss of ABS function.
Bmw Motorsport Division:
BMW M GmbH (formerly BMW Motorsport) division established for racing and high-performance vehicles.
E30 Development:
First M3 model based on a standard production car, developed specifically for Group A touring car racing homologation.
Evolution Models:
M3 (2.3L), M3 Evolution I (2.3L higher output), M3 Evolution II (2.3L further enhanced), M3 Sport Evolution (2.5L), Convertible variants.
Manufacturing Location:
Munich, Germany (BMW AG)
Production Numbers:
Approx. 17,970 units produced across all E30 M3 variants.
Motorsport Legacy:
Dominant in touring car racing globally, including multiple DTM, ETCC, and IMSA championships. Considered one of the greatest homologation specials ever.
Automotive Journalism:
Consistently lauded by automotive press for its driving dynamics, handling, and raw performance. Often features on 'best cars of all time' lists.
Homologation:
Designed and produced to meet FIA Group A homologation requirements for racing.
